added corporate quarterly announcments for the last 4 years

Cargo.toml

@@ -20,6 +20,7 @@ tokio = { version = "1.38", features = ["full"] }
 reqwest = { version = "0.12", features = ["json", "gzip", "brotli", "deflate"] }
 scraper = "0.19"                    # HTML parsing for Yahoo earnings pages
 fantoccini = { version = "0.20", features = ["rustls-tls"] }  # Headless Chrome for finanzen.net
+yfinance-rs = "0.7.2"
 
 # Serialization
 serde = { version = "1.0", features = ["derive"] }

data/exchanges.json

@@ -0,0 +1,260 @@
+{
+  "exchanges": [
+    {
+      "mic": "XNYS",
+      "name": "New York Stock Exchange",
+      "country": "United States",
+      "city": "New York City",
+      "market_cap_trillion_usd": 30.92,
+      "timezone": "America/New_York",
+      "tz_offset": "-05:00",
+      "dst": "Mar–Nov",
+      "open_local": "09:30",
+      "close_local": "16:00",
+      "lunch_break": false,
+      "open_utc": "14:30",
+      "close_utc": "21:00",
+      "currency": "USD"
+    },
+    {
+      "mic": "XNAS",
+      "name": "Nasdaq",
+      "country": "United States",
+      "city": "New York City",
+      "market_cap_trillion_usd": 31.96,
+      "timezone": "America/New_York",
+      "tz_offset": "-05:00",
+      "dst": "Mar–Nov",
+      "open_local": "09:30",
+      "close_local": "16:00",
+      "lunch_break": false,
+      "open_utc": "14:30",
+      "close_utc": "21:00",
+      "currency": "USD"
+    },
+    {
+      "mic": "XSHG",
+      "name": "Shanghai Stock Exchange",
+      "country": "China",
+      "city": "Shanghai",
+      "market_cap_trillion_usd": 7.96,
+      "timezone": "Asia/Shanghai",
+      "tz_offset": "+08:00",
+      "dst": null,
+      "open_local": "09:30",
+      "close_local": "15:00",
+      "lunch_break": "11:30–13:00",
+      "open_utc": "01:30",
+      "close_utc": "07:00",
+      "currency": "CNY"
+    },
+    {
+      "mic": "XJPX",
+      "name": "Japan Exchange Group (Tokyo Stock Exchange)",
+      "country": "Japan",
+      "city": "Tokyo",
+      "market_cap_trillion_usd": 7.06,
+      "timezone": "Asia/Tokyo",
+      "tz_offset": "+09:00",
+      "dst": null,
+      "open_local": "09:00",
+      "close_local": "15:00",
+      "lunch_break": "11:30–12:30",
+      "open_utc": "00:00",
+      "close_utc": "06:00",
+      "currency": "JPY"
+    },
+    {
+      "mic": "XHKG",
+      "name": "Hong Kong Stock Exchange",
+      "country": "Hong Kong",
+      "city": "Hong Kong",
+      "market_cap_trillion_usd": 6.41,
+      "timezone": "Asia/Hong_Kong",
+      "tz_offset": "+08:00",
+      "dst": null,
+      "open_local": "09:30",
+      "close_local": "16:00",
+      "lunch_break": "12:00–13:00",
+      "open_utc": "01:30",
+      "close_utc": "08:00",
+      "currency": "HKD"
+    },
+    {
+      "mic": "XAMS",
+      "name": "Euronext Amsterdam",
+      "country": "Netherlands",
+      "city": "Amsterdam",
+      "market_cap_trillion_usd": 5.61,
+      "timezone": "Europe/Amsterdam",
+      "tz_offset": "+01:00",
+      "dst": "Mar–Oct",
+      "open_local": "09:00",
+      "close_local": "17:30",
+      "lunch_break": false,
+      "open_utc": "08:00",
+      "close_utc": "16:30",
+      "currency": "EUR"
+    },
+    {
+      "mic": "XBSE",
+      "name": "Bombay Stock Exchange",
+      "country": "India",
+      "city": "Mumbai",
+      "market_cap_trillion_usd": 5.25,
+      "timezone": "Asia/Kolkata",
+      "tz_offset": "+05:30",
+      "dst": null,
+      "open_local": "09:15",
+      "close_local": "15:30",
+      "lunch_break": false,
+      "open_utc": "03:45",
+      "close_utc": "10:00",
+      "currency": "INR"
+    },
+    {
+      "mic": "XNSE",
+      "name": "National Stock Exchange of India",
+      "country": "India",
+      "city": "Mumbai",
+      "market_cap_trillion_usd": 5.32,
+      "timezone": "Asia/Kolkata",
+      "tz_offset": "+05:30",
+      "dst": null,
+      "open_local": "09:15",
+      "close_local": "15:d30",
+      "lunch_break": false,
+      "open_utc": "03:45",
+      "close_utc": "10:00",
+      "currency": "INR"
+    },
+    {
+      "mic": "XSHE",
+      "name": "Shenzhen Stock Exchange",
+      "country": "China",
+      "city": "Shenzhen",
+      "market_cap_trillion_usd": 5.11,
+      "timezone": "Asia/Shanghai",
+      "tz_offset": "+08:00",
+      "dst": null,
+      "open_local": "09:30",
+      "close_local": "15:00",
+      "lunch_break": "11:30–13:00",
+      "open_utc": "01:30",
+      "close_utc": "07:00",
+      "currency": "CNY"
+    },
+    {
+      "mic": "XTSE",
+      "name": "Toronto Stock Exchange",
+      "country": "Canada",
+      "city": "Toronto",
+      "market_cap_trillion_usd": 4.00,
+      "timezone": "America/Toronto",
+      "tz_offset": "-05:00",
+      "dst": "Mar–Nov",
+      "open_local": "09:30",
+      "close_local": "16:00",
+      "lunch_break": false,
+      "open_utc": "14:30",
+      "close_utc": "21:00",
+      "currency": "CAD"
+    },
+    {
+      "mic": "XLON",
+      "name": "London Stock Exchange",
+      "country": "United Kingdom",
+      "city": "London",
+      "market_cap_trillion_usd": 3.14,
+      "timezone": "Europe/London",
+      "tz_offset": "+00:00",
+      "dst": "Mar–Oct",
+      "open_local": "08:00",
+      "close_local": "16:30",
+      "lunch_break": false,
+      "open_utc": "08:00",
+      "close_utc": "16:30",
+      "currency": "GBP"
+    },
+    {
+      "mic": "XTAI",
+      "name": "Taiwan Stock Exchange",
+      "country": "Taiwan",
+      "city": "Taipei",
+      "market_cap_trillion_usd": 2.87,
+      "timezone": "Asia/Taipei",
+      "tz_offset": "+08:00",
+      "dst": null,
+      "open_local": "09:00",
+      "close_local": "13:30",
+      "lunch_break": false,
+      "open_utc": "01:00",
+      "close_utc": "05:30",
+      "currency": "TWD"
+    },
+    {
+      "mic": "XSAU",
+      "name": "Saudi Exchange (Tadawul)",
+      "country": "Saudi Arabia",
+      "city": "Riyadh",
+      "market_cap_trillion_usd": 2.73,
+      "timezone": "Asia/Riyadh",
+      "tz_offset": "+03:00",
+      "dst": null,
+      "open_local": "10:00",
+      "close_local": "15:00",
+      "lunch_break": false,
+      "open_utc": "07:00",
+      "close_utc": "12:00",
+      "currency": "SAR"
+    },
+    {
+      "mic": "XFRA",
+      "name": "Deutsche Börse (Xetra)",
+      "country": "Germany",
+      "city": "Frankfurt",
+      "market_cap_trillion_usd": 2.04,
+      "timezone": "Europe/Berlin",
+      "tz_offset": "+01:00",
+      "dst": "Mar–Oct",
+      "open_local": "09:00",
+      "close_local": "17:30",
+      "lunch_break": false,
+      "open_utc": "08:00",
+      "close_utc": "16:30",
+      "currency": "EUR"
+    },
+    {
+      "mic": "XSWX",
+      "name": "SIX Swiss Exchange",
+      "country": "Switzerland",
+      "city": "Zürich",
+      "market_cap_trillion_usd": 1.97,
+      "timezone": "Europe/Zurich",
+      "tz_offset": "+01:00",
+      "dst": "Mar–Oct",
+      "open_local": "09:00",
+      "close_local": "17:30",
+      "lunch_break": false,
+      "open_utc": "08:00",
+      "close_utc": "16:30",
+      "currency": "CHF"
+    },
+    {
+      "mic": "XASX",
+      "name": "Australian Securities Exchange",
+      "country": "Australia",
+      "city": "Sydney",
+      "market_cap_trillion_usd": 1.89,
+      "timezone": "Australia/Sydney",
+      "tz_offset": "+10:00",
+      "dst": "Oct–Apr",
+      "open_local": "10:00",
+      "close_local": "16:00",
+      "lunch_break": false,
+      "open_utc": "00:00",
+      "close_utc": "06:00",
+      "currency": "AUD"
+    }
+  ]
+}

src/config.rs

@@ -15,7 +15,7 @@ impl Default for Config {
     fn default() -> Self {
         Self {
             economic_start_date: "2007-02-13".to_string(),
-            corporate_start_date: "2010-01-01".to_string(),
+            corporate_start_date: "2007-01-01".to_string(),
             economic_lookahead_months: 3,
         }
     }

src/corporate/helpers.rs

@@ -0,0 +1,52 @@
+// src/corporate/helpers.rs
+use super::types::*;
+use chrono::{Local, NaiveDate};
+use std::collections::{HashMap, HashSet};
+
+pub fn event_key(e: &CompanyEvent) -> String {
+    format!("{}|{}|{}", e.ticker, e.date, e.time)
+}
+
+pub fn detect_changes(old: &CompanyEvent, new: &CompanyEvent, today: &str) -> Vec<CompanyEventChange> {
+    let mut changes = Vec::new();
+    let ts = Local::now().format("%Y-%m-%d %H:%M:%S").to_string();
+
+    if new.date.as_str() <= today { return changes; }
+
+    if old.time != new.time {
+        changes.push(CompanyEventChange {
+            ticker: new.ticker.clone(),
+            date: new.date.clone(),
+            field_changed: "time".to_string(),
+            old_value: old.time.clone(),
+            new_value: new.time.clone(),
+            detected_at: ts.clone(),
+        });
+    }
+
+    if old.eps_forecast != new.eps_forecast {
+        changes.push(CompanyEventChange {
+            ticker: new.ticker.clone(),
+            date: new.date.clone(),
+            field_changed: "eps_forecast".to_string(),
+            old_value: format!("{:?}", old.eps_forecast),
+            new_value: format!("{:?}", new.eps_forecast),
+            detected_at: ts.clone(),
+        });
+    }
+
+    if old.eps_actual != new.eps_actual {
+        changes.push(CompanyEventChange {
+            ticker: new.ticker.clone(),
+            date: new.date.clone(),
+            field_changed: "eps_actual".to_string(),
+            old_value: format!("{:?}", old.eps_actual),
+            new_value: format!("{:?}", new.eps_actual),
+            detected_at: ts.clone(),
+        });
+    }
+
+    // Add similar for revenue if applicable
+
+    changes
+}

src/corporate/mod.rs

@@ -3,6 +3,7 @@ pub mod types;
 pub mod scraper;
 pub mod storage;
 pub mod update;
+pub mod helpers;
 
 pub use types::*;
 pub use update::run_full_update;

src/corporate/scraper.rs

@@ -2,8 +2,10 @@
 use super::types::{CompanyEvent, CompanyPrice};
 use fantoccini::{Client, Locator};
 use scraper::{Html, Selector};
-use chrono::{NaiveDate, Datelike};
+use chrono::{NaiveDate};
 use tokio::time::{sleep, Duration};
+use yfinance_rs::{YfClient, Ticker, Range, Interval};
+use yfinance_rs::core::conversions::money_to_f64;
 
 const USER_AGENT: &str = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36";
 
@@ -54,9 +56,9 @@ pub async fn fetch_earnings_history(client: &Client, ticker: &str) -> anyhow::Re
         let cols: Vec<String> = row.select(&Selector::parse("td").unwrap())
             .map(|td| td.text().collect::<Vec<_>>().join(" ").trim().to_string())
             .collect();
-        if cols.len() < 6 { continue; }
+        if cols.len() < 4 { continue; }
 
-        let full_date = &cols[2];
+        let full_date = &cols[0];
         let parts: Vec<&str> = full_date.split(" at ").collect();
         let raw_date = parts[0].trim();
         let time_str = if parts.len() > 1 { parts[1].trim() } else { "" };
@@ -66,8 +68,8 @@ pub async fn fetch_earnings_history(client: &Client, ticker: &str) -> anyhow::Re
             Err(_) => continue,
         };
 
-        let eps_forecast = parse_float(&cols[3]);
+        let eps_forecast = parse_float(&cols[1]);
-        let eps_actual = if cols[4] == "-" { None } else { parse_float(&cols[4]) };
+        let eps_actual = if cols[2] == "-" { None } else { parse_float(&cols[2]) };
 
         let surprise_pct = if let (Some(f), Some(a)) = (eps_forecast, eps_actual) {
             if f.abs() > 0.001 { Some((a - f) / f.abs() * 100.0) } else { None }
@@ -85,7 +87,7 @@ pub async fn fetch_earnings_history(client: &Client, ticker: &str) -> anyhow::Re
             ticker: ticker.to_string(),
             date: date.format("%Y-%m-%d").to_string(),
             time,
-            period: "".to_string(),  // No period info available, set to empty
+            period: "".to_string(),
             eps_forecast,
             eps_actual,
             revenue_forecast: None,
@@ -98,38 +100,46 @@ pub async fn fetch_earnings_history(client: &Client, ticker: &str) -> anyhow::Re
     Ok(events)
 }
 
-pub async fn fetch_price_history(client: &Client, ticker: &str, start: &str, end: &str) -> anyhow::Result<Vec<CompanyPrice>> {
+pub async fn fetch_price_history(
-    let start_ts = NaiveDate::parse_from_str(start, "%Y-%m-%d")?
+    ticker: &str,
-        .and_hms_opt(0, 0, 0).unwrap().and_utc()
+    start: &str,
-        .timestamp();
+    end: &str,
+) -> anyhow::Result<Vec<CompanyPrice>> {
+    let client = YfClient::default();
+    let tk = Ticker::new(&client, ticker);
 
-    let end_ts = NaiveDate::parse_from_str(end, "%Y-%m-%d")?
+    // We request the maximum range – the library will automatically respect Yahoo's limits
-        .succ_opt().unwrap()
+    let history = tk
-        .and_hms_opt(0, 0, 0).unwrap().and_utc()
+        .history(Some(Range::Max), Some(Interval::D1), true)
-        .timestamp();
+        .await
+        .map_err(|e| anyhow::anyhow!("Yahoo Finance API error for {ticker}: {e:?}"))?;
 
-    let url = format!(
+    let mut prices = Vec::with_capacity(history.len());
-        "https://query1.finance.yahoo.com/v7/finance/download/{ticker}?period1={start_ts}&period2={end_ts}&interval=1d&events=history&includeAdjustedClose=true"
-    );
 
-    client.goto(&url).await?;
+    for candle in history {
-    let csv = client.source().await?;
+        let date_str = candle.ts.format("%Y-%m-%d").to_string();
+
+        // Filter by user-defined start / end
+        if date_str < (*start).to_string() || date_str > (*end).to_string() {
+            continue;
+        }
 
-    let mut prices = Vec::new();
-    for line in csv.lines().skip(1) {
-        let cols: Vec<&str> = line.split(',').collect();
-        if cols.len() < 7 { continue; }
         prices.push(CompanyPrice {
             ticker: ticker.to_string(),
-            date: cols[0].to_string(),
+            date: date_str,
-            open: cols[1].parse()?,
+            open: money_to_f64(&candle.open),
-            high: cols[2].parse()?,
+            high: money_to_f64(&candle.high),
-            low: cols[3].parse()?,
+            low: money_to_f64(&candle.low),
-            close: cols[4].parse()?,
+            // close_unadj is the raw (non-adjusted) close; close is the adjusted one
-            adj_close: cols[5].parse()?,
+            close: money_to_f64(&candle.close_unadj.unwrap_or(candle.close.clone())),
-            volume: cols[6].parse()?,
+            adj_close: money_to_f64(&candle.close),
+            volume: candle.volume.unwrap_or(0),
         });
     }
+
+    // Sort just in case (normally already sorted)
+    prices.sort_by_key(|p| p.date.clone());
+
     Ok(prices)
 }
 

src/corporate/storage.rs

@@ -1,11 +1,11 @@
 // src/corporate/storage.rs
-use super::types::{CompanyEvent, CompanyPrice};
+use super::types::{CompanyEvent, CompanyPrice, CompanyEventChange};
-use std::collections::{HashMap, HashSet};
+use super::helpers::*;
 use tokio::fs;
-use chrono::{Local, NaiveDate};
+use chrono::{Local, NaiveDate, Datelike};
+use std::collections::HashMap;
 
-/// Load all events from disk into a HashMap<ticker|date, event>
+pub async fn load_existing_events() -> anyhow::Result<HashMap<String, CompanyEvent>> {
-async fn load_all_events_map() -> anyhow::Result<HashMap<String, CompanyEvent>> {
     let mut map = HashMap::new();
     let dir = std::path::Path::new("corporate_events");
     if !dir.exists() {
@@ -16,11 +16,12 @@ async fn load_all_events_map() -> anyhow::Result<HashMap<String, CompanyEvent>>
     while let Some(entry) = entries.next_entry().await? {
         let path = entry.path();
         if path.extension().and_then(|s| s.to_str()) == Some("json") {
-            let content = fs::read_to_string(&path).await?;
+            let name = path.file_name().and_then(|n| n.to_str()).unwrap_or("");
-            if let Ok(events) = serde_json::from_str::<Vec<CompanyEvent>>(&content) {
+            if name.starts_with("events_") && name.len() == 17 { // events_yyyy-mm.json
+                let content = fs::read_to_string(&path).await?;
+                let events: Vec<CompanyEvent> = serde_json::from_str(&content)?;
                 for event in events {
-                    let key = format!("{}|{}", event.ticker, event.date);
+                    map.insert(event_key(&event), event);
-                    map.insert(key, event);
                 }
             }
         }
@@ -28,34 +29,68 @@ async fn load_all_events_map() -> anyhow::Result<HashMap<String, CompanyEvent>>
     Ok(map)
 }
 
-/// Merge new events with existing ones and save back to disk
+pub async fn save_optimized_events(events: HashMap<String, CompanyEvent>) -> anyhow::Result<()> {
-pub async fn merge_and_save_events(ticker: &str, new_events: Vec<CompanyEvent>) -> anyhow::Result<()> {
-    let mut existing = load_all_events_map().await?;
-
-    // Insert or update
-    for event in new_events {
-        let key = format!("{}|{}", event.ticker, event.date);
-        existing.insert(key, event);
-    }
-
-    // Convert back to Vec and save (simple single file for now)
-    let all_events: Vec<CompanyEvent> = existing.into_values().collect();
     let dir = std::path::Path::new("corporate_events");
     fs::create_dir_all(dir).await?;
-    let path = dir.join("all_events.json");
+
-    let json = serde_json::to_string_pretty(&all_events)?;
+    // Delete old files
-    fs::write(&path, json).await?;
+    let mut entries = fs::read_dir(dir).await?;
+    while let Some(entry) = entries.next_entry().await? {
+        let path = entry.path();
+        let name = path.file_name().and_then(|n| n.to_str()).unwrap_or("");
+        if name.starts_with("events_") && path.extension().map(|e| e == "json").unwrap_or(false) {
+            fs::remove_file(&path).await?;
+        }
+    }
+
+    let mut sorted: Vec<_> = events.into_values().collect();
+    sorted.sort_by_key(|e| (e.ticker.clone(), e.date.clone()));
+
+    let mut by_month: HashMap<String, Vec<CompanyEvent>> = HashMap::new();
+    for e in sorted {
+        if let Ok(d) = NaiveDate::parse_from_str(&e.date, "%Y-%m-%d") {
+            let key = format!("{}-{:02}", d.year(), d.month());
+            by_month.entry(key).or_default().push(e);
+        }
+    }
+
+    for (month, list) in by_month {
+        let path = dir.join(format!("events_{}.json", month));
+        fs::write(&path, serde_json::to_string_pretty(&list)?).await?;
+    }
     Ok(())
 }
 
-/// Save price history for a single ticker (overwrite old file)
+pub async fn save_changes(changes: &[CompanyEventChange]) -> anyhow::Result<()> {
-pub async fn save_prices_for_ticker(ticker: &str, prices: Vec<CompanyPrice>) -> anyhow::Result<()> {
+    if changes.is_empty() { return Ok(()); }
+    let dir = std::path::Path::new("corporate_event_changes");
+    fs::create_dir_all(dir).await?;
+
+    let mut by_month: HashMap<String, Vec<CompanyEventChange>> = HashMap::new();
+    for c in changes {
+        if let Ok(d) = NaiveDate::parse_from_str(&c.date, "%Y-%m-%d") {
+            let key = format!("{}-{:02}", d.year(), d.month());
+            by_month.entry(key).or_default().push(c.clone());
+        }
+    }
+
+    for (month, list) in by_month {
+        let path = dir.join(format!("changes_{}.json", month));
+        let mut all = if path.exists() {
+            let s = fs::read_to_string(&path).await?;
+            serde_json::from_str(&s).unwrap_or_default()
+        } else { vec![] };
+        all.extend(list);
+        fs::write(&path, serde_json::to_string_pretty(&all)?).await?;
+    }
+    Ok(())
+}
+
+pub async fn save_prices_for_ticker(ticker: &str, mut prices: Vec<CompanyPrice>) -> anyhow::Result<()> {
     let dir = std::path::Path::new("corporate_prices");
     fs::create_dir_all(dir).await?;
     let path = dir.join(format!("{}.json", ticker));
 
-    // Optional: sort by date
-    let mut prices = prices;
     prices.sort_by_key(|p| p.date.clone());
 
     let json = serde_json::to_string_pretty(&prices)?;

src/corporate/types.rs

@@ -31,7 +31,7 @@ pub struct CompanyPrice {
 pub struct CompanyEventChange {
     pub ticker: String,
     pub date: String,
-    pub field: String,                   // "time", "eps_forecast", "eps_actual", "new_event"
+    pub field_changed: String,                   // "time", "eps_forecast", "eps_actual", "new_event"
     pub old_value: String,
     pub new_value: String,
     pub detected_at: String,

src/corporate/update.rs

@@ -1,31 +1,83 @@
 // src/corporate/update.rs
-use super::{scraper::*, storage::*, types::*};
+use super::{scraper::*, storage::*, helpers::*, types::*};
 use crate::config::Config;
 
 use chrono::Local;
-use std::collections::{HashMap, HashSet};
+use std::collections::HashMap;
-
 
 pub async fn run_full_update(client: &fantoccini::Client, tickers: Vec<String>, config: &Config) -> anyhow::Result<()> {
     println!("Updating {} tickers (prices from {})", tickers.len(), config.corporate_start_date);
 
     let today = chrono::Local::now().format("%Y-%m-%d").to_string();
 
-    for ticker in tickers {
+    let mut existing = load_existing_events().await?;
+
+    for ticker in &tickers {
         print!("  → {:6} ", ticker);
 
-        // Earnings
+        if let Ok(new_events) = fetch_earnings_history(client, ticker).await {
-        if let Ok(events) = fetch_earnings_history(client, &ticker).await {
+            let result = process_batch(&new_events, &mut existing, &today);
-            merge_and_save_events(&ticker, events.clone()).await?;
+            save_changes(&result.changes).await?;
-            println!("{} earnings", events.len());
+            println!("{} earnings, {} changes", new_events.len(), result.changes.len());
         }
 
-        // Prices – now using config.corporate_start_date
+        if let Ok(prices) = fetch_price_history(ticker, &config.corporate_start_date, &today).await {
-        if let Ok(prices) = fetch_price_history(client, &ticker, &config.corporate_start_date, &today).await {
+            save_prices_for_ticker(ticker, prices).await?;
-            save_prices_for_ticker(&ticker, prices).await?;
         }
 
         tokio::time::sleep(tokio::time::Duration::from_millis(250)).await;
     }
+
+    save_optimized_events(existing).await?;
     Ok(())
+}
+
+pub struct ProcessResult {
+    pub changes: Vec<CompanyEventChange>,
+}
+
+pub fn process_batch(
+    new_events: &[CompanyEvent],
+    existing: &mut HashMap<String, CompanyEvent>,
+    today: &str,
+) -> ProcessResult {
+    let mut changes = Vec::new();
+
+    for new in new_events {
+        let key = event_key(new);
+
+        if let Some(old) = existing.get(&key) {
+            changes.extend(detect_changes(old, new, today));
+            existing.insert(key, new.clone());
+            continue;
+        }
+
+        // Check for time change on same date
+        let date_key = format!("{}|{}", new.ticker, new.date);
+        let mut found_old = None;
+        for (k, e) in existing.iter() {
+            if format!("{}|{}", e.ticker, e.date) == date_key && k != &key {
+                found_old = Some((k.clone(), e.clone()));
+                break;
+            }
+        }
+
+        if let Some((old_key, old_event)) = found_old {
+            if new.date.as_str() > today {
+                changes.push(CompanyEventChange {
+                    ticker: new.ticker.clone(),
+                    date: new.date.clone(),
+                    field_changed: "time".to_string(),
+                    old_value: old_event.time.clone(),
+                    new_value: new.time.clone(),
+                    detected_at: Local::now().format("%Y-%m-%d %H:%M:%S").to_string(),
+                });
+            }
+            existing.remove(&old_key);
+        }
+
+        existing.insert(key, new.clone());
+    }
+
+    ProcessResult { changes }
 }